Core drill



Feb. 5, 1935. G. G. HARRINGTON 1,989,982

CORE DRILL Filed May l, 1933 2 Sheets-Sheet l George G. Harrinjfon INVENTOR.

ATTORNEY.

""I'H" I Feb.

5, 1935. G. G. HARRINGToN 1,989,982

CORE DRILL Filed May 1, 193s 2 sheets-sheet 2 HR L am NE m ,w a A H M 4 c e 1 w Pu been moved Patented Feb. 5, 1935 CORE DRILL George G. Harrington,

to Reed corporation of Texas Houston, Tex., assignor Roller Bit Company, Houston, Tex., a

Application May 1, 1933, Serial No. 668,705

11 claims. (c1. c55-12) This invention relates generally to deep well drilling apparatus and specifically to core drills.

Conventional deep well core drills comprise a drill stem, a bit secured to the lower end thereof having a central opening and a core barrel Within the stem to receive and retain the core of the formation entering through lsaid opening. In the upper end of the core barrel is a relief valve serving to permit the escape from the barrel of fluid that would otherwise be confined therein and to prevent the passage from the interior of the drill stem into the barrel of the muddy Water known as slush that is pumped through the drill stem and bit during drilling operations. It is desirable to wash out the core barrel after the d'rill stem has been lowered into the well and before drilling is commenced by pumping slush downwardly through the drill stem and core barrel, but this cannot be done with the conventional core drill because the relief valve will not permit the slush to enter the core barrel. This invention has for one of its objects the provision of a core drill embodying new and improved means whereby the relief valve will be held away from its seat so that slush may be pumped downwardly through the drill stem and core barrel to wash out the latter and then released by movement of the drill stem to performits usual function during drilling operations.

Conventional core drills also include a device known as a core catcher which permits a portion of the formation known as the core to enter the core barrel but prevents its escape therefrom. Another object of this invention is to provide new and improved means whereby the core catcher may be positively moved into its core catching position bymovement of the drill stem.

Other objects will hereinafter appear.

The preferred embodiment of the invention is illustrated by the accompanying drawings wherein Fig. 1 is` a fragmentary sectional elevation of the core drill, the parts being shown in theV positions they occupy when the core barrel is being washed. Fig. 2 is a view similar to Fig. 1, the parts being shown in the positions they occupy during the drilling operation; Fig. 3 is a view similar to Fig. l, the parts being shown in the positions they occupy after the core has entered the core barrel and the core catcher has into its active position; Fig. 4 is a detail view illustrating the interengaging clutch teeth carried by the drill stem sections; and Fig. 5 is a horizontal section on the line 5-5 of Fig. 3.

In the drawings the upper and lower telescopic sections of the drill stem are indicated at l and 2. The section 1 has a reduced extension 3 slidable vertically in the lower section 2 and threaded therein as indicated at 4. In order to seal the upper section l to the lower section 2 a 5 pipe-5 may be threaded in the part 3 to extend into the lower section 2. Between the pipe 5 and the lower section 2 may be placed a packing 6 compressed by a gland 7. An annular flange 8 may be provided on the lower end of the pipe 5 to prevent inadvertent disconnection of the sections l and 2.

On the lower end of the section2 is secured a bit 9 having a central bore 10 for the reception of the core and having passageways. 11 through which the slush is pumped during drilling operations. Adjacent the bore is a core catcher 12 comprising a plurality of lingers 13 pivoted as indicated at 14 to a metal ring 15 and having rubber 16 molded therein to yieldably hold them in inactive position. Within the drill stem is a core barrel 17 resting on the core catcher 12 and having grooves 18 to permit the passage of slush to the bit passageways 11. The core barrel is extended upwardly through the pipes 5 and 3 into the upper 25 i section 1. The relief valve is shown at 19. Its rod 20 is mounted in the cross head 21 secured to the sleeve 22. The valve spring 23 lserves to yieldably hold the valve 19 away from the Ycross head 21. The sleeve 22 is normally held in its up- 30 permost position shown by Fig. 1 by the spring 24. The numeral 25 indicates a detent adapted to enter groove 26 in sleeve 22 to hold the sleeve in its lowermost inactive position after it has been moved therein. By the valve holding means just 30 described the` valve `19 is normally held away from its seat 2'7 so that fluid may be pumped through the openings 28 and past valve 19 into the core barrel 1'7. Pivoted within the upper section 1 as indicated at 29 are dogs 30 urged inwardly by springs 31 and engaging the sleeve 22' as shown by Fig. 1. The dogs 30 are also arranged to engage the shoulders 32 of the core barrel as shown by Fig. 3. Carried by the upper and lower sections 1 and 2 are clutch teeth 33 and 34 respectively for the purposes which will hereinafter appear.

The drill is used as follows:

The drill having been lowered .into a position in the well at which the bit 9 is a short distance above the bottom of the well, slush is pumped by the conventional means through the drill stem. The parts then being in the position shown by Fig. 1, the slush enters the openings 28, passes the relief valve l19 and passes through the core barrel active position by the detent 17 to wash the latter. Then the drill stem is lowered until the bit 9 is on the bottom of the well and then rotated.A The threads, 4 will be thereby disengaged and the upper section l is then free to descend from the position shown by Fig. 1 to the position shown by Fig. 2. The connecting means 30 are thereby made to move the relief valve holding means 22 downwardly against the resistance of spring 24 so that the relief valve 19 will be in the position shown by Fig. 2. The clutch teeth 33 and 34 are also thereby moved into engagement with each other. And so when the drill stem is rotated the bit 9 will be rotated and the core of the formation will enter the core barrel 17. As the core enters the core barrel 17 the spring 23 will permit the escape from the core barrel of any uid that would otherwise be trapped therein but will prevent theentrance into that is meanwhile the core barrel of the slush pumped downwardly through the drill stem and out of the slush passageways 11 in the bit to keep the bit cool and to remove the cuttings thereof.

After the core has entered the core barrel the drill stem may then be elevated to effect the engagement of the -connecting means 30 and the shoulder 32 of the core barrel. 'Ihis engagement is not interfered with by the relief valve holding means 22 because said means 22 is held in its in- 25. Then the drill stem is lowered and connecting means 30 is made to move the core barrel 17 downwardly into the position shown by Fig. 3 to collapse the core' catcher l2 to trap the core in the core barrel. The drill may then be removed from the well with the core in the core barrel. 4

'I'he invention is not limited to the preferred embodiment herein disclosed. Various changes may be made within the scope of thev following claims.

1. A core drill including a drill stem having upper and lower telescopic sections; a bit secured to the lower of said sections; a core barrel in said drill stem; a relief valve in said core barrel; a collapsible core catcher in said bit below said core barrel; a relief valve holding sleeve movable on said core barrel; a spring to cause said sleeve to hold said relief valve open to permit fluid to be pumped through said core barrel when said sections are lin predetermined positions with respect to each other; connectingdogs pivoted in said upper section to engage and connect said valve holding sleeve and said core barrel to said upper section; interengaging clutch teeth carried by said sections to impart rotation from said upper section to said lower section; said clutch teeth being out of engagement with each other. and said connecting dogs being in engagement with said valve holding sleeve and being held out of engagement with said core barrel by said-valve holding sleeve when said sections are in said positions; threads between said sections to hold said sections in said positions; said threads being disengageable by rotation of said upper section with respect to said lower section; saidupper section being thereupon movable toward said lower section to effect the engagement of said clutch teeth and .to cause said connecting dogs to move said valve holding sleeve into a position to permit closure of said valve, so that said bit may be rotated and uid pumped through said drill but not through said core barrel; means to hold said valve holding sleeve in said position; said connecting dogs being engageable with said core barrel when said valve holding sleeve is in said position and said upper section is moved away from said lower section, so that said upper section may again be v moved toward said lower section to cause said connecting dogs to move said core barrel downwardly to collapse said core catcher.

2. A core drill including a drill stem having upper and lower telescopic sections; a bit secured to the lowery of said sections; a core barrel in said drill stem; a relief valve in said core barrel; a collapsible core catcher in said bit below said core barrel; relief valve holding means to hold said relief valve open to permit uid to be pumped through said core barrel when said sections are in predetermined positions with respect to each other; connecting means to connect said valve holding means and said core barrel to said upper section; interengaging means carried by said sections to impart rotation from said upper section Vto said lower section; said interengaging means being out of engagement with each other and said connecting means being in engagement with said valve holding means and being held out of engagement with said core barrel by said valve holding means when said sections are in said positions; threads between said sections to hold said sections in said positions; said threads being disengageable by rotation ofv said upper section with respect to said lower section; said Aupper section being thereupon movable toward said lower section to effect the engagement of said interengaging means and to cause said connecting means to move said valve holding means into 'a position to permit closure of said valve; so that said bit may be rotated and uid pumped through said drill but not through-said core barrel; means tov hold said valve holding means in said position; said connecting means .being engageable with said core barrel when said valve holding means is in said position and said upper section is moved away from said lower section so that said upper section may again be moved toward said lower section to cause said connecting means to move said core barrel downwardly to collapse said core catcher.

3. A core drill including a drill stem havingy upper and lower sections movable with respect to each other; a bit secured to the lower of said sections; a core barrel in said drill stem; a relief valve in said core barrel; a collapsible core catcher in said bit below said core barrel; relief valve holding means to hold said valve .open to permit fluid to be pumped through said core barrel when said sections are in predetermined positions with respect to each other; connecting means to connect said valve holding means and said core barrel to said upper section; interengaging means carried by said sections to impart rotation from said upper section to said lower section; said interengaging means being out of engagement with each other when said sections are in said pasitions; threads between said sections to hold said sections in said positions; said threads being disengageable by rotation of said upper section with respect to said lower section; said upper section being thereupon movable toward said lower section to effect the engagement of said interengaging means and to cause said connecting means to move said valve holding means into a position to permit closure of said valve so that said bit may be rotated and'fluid may be pumped through said drill but not through said core barrel; said upper section being movable with respect to said lower section to cause said connecting means'to move said core barrel downwardly to collapse said core catcher.

impart rotation a relief valve for said core upper and lower sections movable with respect to each other; a bit secured to the lower of said sections; a core barrel in said drill stem; a relief valve in said core barrel; a core catcher; relief valve holding means to hold said relief valve open to permit fluid to be pumped through said core barrel when said sections are in predetermined positions with respect to each other; connecting means operatively associated with said sections; interengaging means carried by said sections to from said upper section to said said interengaging means being out of engagement with each other when said sections are in said positions; releasable means between said sections to hold said sections in said positions; said releasable means being disengageable by movement of said upper section with respect to said lower section; said upper section being thereupon movable with respect to said lower section to effect the engagement of said interengaging means and to cause said connecting means to move said valve holding means to permit closure of said valve so that said bit may be rotated and fluid may be pumped through said drill but not through said core barrel; said upper section being movable with respect to said lower section to cause said connecting means to actuate said core catcher.

5. A core drill including a drill stem having sections movable with respect to each other; a core barrel in said drill stem; a core catcher and barrel; relief valve holding means to hold said valve open; and means operatively associated with said sections to cause said valve holding means to permit closure of said valve, and to actuate said core catcher, when said sections are moved with respect to each other.

6. A core drill including a drill stem having sections movable with respect to each other; a bit on the lower end of said drill stem a core barrel in said drill stemand forming therewith a ilu'id passageway to said bit; a relief valve in said core barrel; means to hold said relief valve open; and means operatively associated with said sections to cause said valve holding means to permit closure of said valve when said sections are moved with respect to each other.

7. A core drill having a drill stem; a core barrel in' said drill stem; a valve in and adjacent to the upper end of said core barrel; a valve holding sleeve movable on said core barrel; yieldable means to cause said sleeve to hold said valve open; and means to move said sleeve to close said valve.

8. A core drill including a drill stem having upper and lower sections movable with respect to each other; a bit secured to the lower of said sections; a core barrel in said drill stem; a core catcher in said bitl below said core barrel; interengaging means between said sections whereby rotation of said upper section is imparted to said lower section; threads between said sections to hold said sections in predetermined positions with respect to each other; said interengaging means being out of engagement with each other when said sections are in said positions; connecting lower section;

to be pumped from said means between said upper section and said core barrel; said threads being disengageable by rotation vof said upper section with respect to said lower section; means to prevent the connection of said upper section and said core barrel by said connecting means when said threads are disengaged and said upper section is rst moved toward said lower section, and to permit said connection when said upper section is then moved away from said lower section and back toward said lower section to cause said core barrel to actuate said core catcher.

9. A core drill including a drill stem having upper and lower sections movable with respect to each other; a means to allow fluid circulation through said barrel; a core catcher; means operatively associated with said sections to actuate said core catcher; said means being inactive when said upper section is first moved toward said lower section and active when said upper section is then moved away .from and back toward said lower section; means operated by the movement of said sections to close said fluid circulating means; and additional means inactive during the rst movement of said sections but actuated by the subsequent movement of said sections to actuate the core catcher into core cutting position. y

10. A core drill including a drill stem having upper and lower sections movable with respect to each other; a bit secured to the lower end of said stern; a core barrel in said drill stem; a. relief valve in said core barrel; .a relief valve hold-'- ing means to hold said valve open to permit uid drill stem through said core barrel when said sections are in pre-determined positions with respect to each other; and releasable means to hold said sections in said positions when said drill is being lowered in the well; said means being releasable by rotation of said upper section with respect to said lower section when said bit is on the bottom of the well to permit said upper section to be moved toward said lower section to cause said relief valve holding means to permit closure of said valve;said drill stem and core barrel then forming a fluid passageway to said bit.

11. A core drill including a. drill stem having sections` movable with respect to each other; a bit secured to the lower end of said stem; a core lbarrel in said drill stem; a relief valve in said core barrel; a relief valve holding means to hold said valve open to permit fluid to be pumped from said drillstem through said core barrel when said sections are in tions with respect to each other; and releasable means to hold said sections in said positions when said drill is being lowered in the well; said means being releasable when said bit is on the bottom of the well to permit said sections to be moved with resect to each other to cause said relief valve holding means to permit closure of said valve; said drill stem and core barrel then forming a fluid pasageway to said bit.

GEORGE G. HARRINGTON.

core barrel in said drill stem;

predetermined posif 

